Abstract: The disclosed fin and nozzle unit comprises a generally cylindrical nozzle body having an axial nozzle opening therein for discharging a gaseous propulsion stream, a plurality of fins having pivot means mounting such fins on a rear end portion of the nozzle body for swinging movement between retracted launch positions and extended flight positions in which such fins are swung outwardly from the launch positions through a predetermined angle, such fins having bent or skewed portions which are positioned in the gaseous propulsion stream when the fins are in their retracted launch positions for causing the gaseous propulsion stream to act upon the bent portions so as to produce spinning movement of the rocket when it is being launched, the bent portions being movable outwardly out of the gaseous propulsion stream when the fins are swung outwardly into their extended flight positions to avoid imparting further spin to the rocket during flight.

Abstract: An electronic time opener and opener system is utilized for initiating the pening of a plurality of munition cannisters at an accurate settable time after ejection from a high speed aircraft. Analogue circuitry is used in the opener setter to measure the capacitance of an RC circuit of the electronic time opener, immediately prior to cannister ejection. Upon the basis of this pre-ejection measurement a proper voltage charge is generated to obtain sufficient energy to actuate a detonator in the munition at the proper time. The combined opener and opener setter system permit accurate tuning while using wide tolerance capacitance components in the electronic time opener.